60 
former, the amount available to the tree is probably not by any means as 
great, owing to the difference in porosity. In view of the large amount 
of water necessary to the life of the coconut tree, one would naturally 
expect it to grow better in an easily permeable soil rather than in one 
from which water and soluble nutriment can only be taken up with 
difficulty. The objection has been raised that according to chemical 
analyses the soils near the sea do not appear to contain sufficient plant 
food to support life of any kind, much less that of a large and heavily 
productive tree like the coconut. 
From analyses of coconuts made at this Bureau we have found that 
nuts from San Ramon contain nitrogen, potash, and phosphoric acid in 
approximately the following amounts: 
| 7 | | 
|  Phos- 
Part. Nitrogen. Potash. — phoric | 
| acid. 
- us. os | a | 
Grams, | Grams. Grams, 
PMO ete eee cuss -| 1. 609 | 3.915 0.017 
Shell os eeswote-se | 660 . 947 . 459 
Meat eee seesut ass. 4. 683 | 2.475 1.740 
MK. on. oto 2 Sae5 se 1.542 1.318 | .171 | 
Total __---------- 8.494 8. 650 | 2,387 | 
In 1 hectare of land on which about 173 trees are growing and produc- 
ing, a total of about 7,000 nuts per annum may be expected.* Under 
these conditions there is exhausted from the soil by the nuts alone a 
total of — 
Kilos 
Lf 04 | ea ane oe er © so lansntcdectseudsetensd2 Gemeteteeneneeenstsse- 59.43 
Pb occcndeeveceseeeksde seosavebseceadsyoasgeescooceccenestsesaeceess'qnseahemeeeeciegeesntsissas<se 60.55 
Phosphoric acid ............---.:-ssccsceseeseseceseseeeeseceneeeesenensnanennansnsanenenenencsss 16.73 
In addition to this there is a large weight of material withdrawn by 
falling leaves. Each tree on an average will lose annually 16 leaves, 
weighing about 3 kilos each, making about 8,800 kilos per year lost by 
173 trees. Analysis shows that in this weight of dry leaves there is 
approximately— 
Kilos 
Nitrogen .........---c-ccecceeseresssssssecesenecescenseecpeeesessscnescssaanannsarsesesneseneesees 31.69 
POtash <..c0ccscccccsccvosdesensccsezscsasseseetssseesnenccctehscenaudonatocsneppetmersageeiedwsantensees 74.82 
Phosphoric acid ...........---ccccccecseesesessseeessseeseneneneneecesnnnaeacacanenenennecsstes 24.65 
We have then a total annual drain on the soil per hectare of— 
Kilos. 
Nitrogen ...........---c-cecececeeceseseeeeeneeesceceesseenseseenenssenennensnmenenenansuanaseborernses 91.12 
Potash -.....cccececccsetccssecceeccasectsceecsaece-nacsetcaneeeecoencse to sgeieennnaetammitenger=> <7 135.37 
Phosphoric acid .............-...csces-ceceeeseseeeeeeeeeeeeeeeeneenenes tomensateddnrareneoreree 41.38 
‘See the paper by E. B. Copeland on the character of the roots of the Cocos. 
°'This is on the basis of 40 nuts per tree per annum, a very high average for 
San Ramon trees. 
